平衡点

存在条件

$E_{1}^{*}, E_{2}^{*}$

$Δ > 0$

case1: $ρ_{1} < 0, ρ_{1}^{2} > 3 B ρ_{2}$

case2: $ρ_{1} > 0, ρ_{2} < 0$

$E_{1}^{*} = E_{2}^{*}$

$Δ = 0$

case1: $ρ_{1} < 0, ρ_{1}^{2} > 3 B ρ_{2}$

case2: $ρ_{1} > 0, ρ_{2} < 0$